# std::iscntrl(std::locale)

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< cpp‎ | locale

Defined in header `<locale>` |  |
template< class CharT > bool iscntrl( CharT ch, const locale& loc ); |  |

Checks if the given character is classified as a control character by the given locale's std::ctype facet.

### Parameters

ch | - | character
loc | - | locale

### Return value

Returns true if the character is classified as a control character, false otherwise.

### Possible implementation

    template<class CharT>
    bool iscntrl(CharT ch, const std::locale& loc)
    {
        return std::use_facet<std::ctype<CharT>>(loc).is(std::ctype_base::cntrl, ch);
    }

### Example

Demonstrates the use of `iscntrl()` with different locales (OS-specific).

Run this code

    #include <iostream>
    #include <locale>

    int main()
    {
        const wchar_t CCH = L'\u0094'; // Destructive Backspace in Unicode

        std::locale loc1("C");
        std::cout << "iscntrl(CCH, C locale) returned "
                  << std::boolalpha << std::iscntrl(CCH, loc1) << '\n';

        std::locale loc2("en_US.UTF8");
        std::cout << "iscntrl(CCH, Unicode locale) returned "
                  << std::boolalpha << std::iscntrl(CCH, loc2) << '\n';
    }

Possible output:

    iscntrl(CCH, C locale) returned false
    iscntrl(CCH, Unicode locale) returned true

### See also

iscntrl | checks if a character is a control character (function)
iswcntrl | checks if a wide character is a control character (function)

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